How the Aztec Empire Rose and Fell in Under Two Centuries
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In 1325 a wandering people settled on a marshy island in a lake in central Mexico because, their priests said, they had seen an eagle perched on a cactus there. Two centuries later their city, Tenochtitlan, had perhaps 200,000 inhabitants, more than any city in Spain, and ruled over several million people through a web of alliances and tribute. Two years after the Spanish arrived, it was rubble. The speed of both the rise and the fall is the thing to explain.
Latecomers in an old world
The people we call Aztecs called themselves Mexica, and they arrived late in a region that had seen cities for two thousand years. Teotihuacan, whose pyramids still stand north of Mexico City, had held 100,000 people before 600 CE; the Toltecs had followed; by the 1300s the Valley of Mexico was a patchwork of city-states around a system of lakes, all speaking Nahuatl and sharing gods, calendars and a taste for warfare. The Mexica were poor migrants from the north who hired themselves out as mercenaries and were tolerated on land nobody else wanted.
The island turned out to be an asset. It was defensible, the lake gave fish and waterfowl, and the Mexica built chinampas, raised fields of mud and vegetation piled up in the shallows, that produced several crops a year and eventually fed a vast city. Causeways linked the island to the shore, and an aqueduct brought fresh water from the springs at Chapultepec.
The Triple Alliance
In 1428 the Mexica joined two neighbouring cities, Texcoco and Tlacopan, to overthrow the dominant power in the valley, and the Triple Alliance they formed is what the word empire really refers to. Over the next ninety years it conquered outward in every direction, reaching both coasts, and the Mexica ruler became the senior partner. The empire did not govern its conquests directly. Defeated cities kept their rulers and their gods and paid tribute, cotton cloth, maize, cacao, feathers, gold, jade, warriors, and the tribute lists that survive show the flow of wealth into Tenochtitlan.
Warfare was constant and had a religious dimension. The gods, the Mexica believed, required human blood to keep the sun moving, and the flower wars, ritualised battles fought with neighbouring states, supplied captives for sacrifice at the Great Temple at the city's heart. The scale is debated; the fact is not. It also meant the empire never lacked enemies, and the cities it had defeated but not absorbed, above all Tlaxcala, which it had never conquered, remembered.
A city on the water
The Spaniards who first saw Tenochtitlan in 1519 compared it to Venice and to the enchanted cities in the romances they had read. Bernal Diaz, a soldier who wrote his memoir decades later, said some of the men asked whether they were dreaming. The city had straight canals and streets, a great market at Tlatelolco that a Spaniard estimated held 60,000 people a day, palaces, zoos, botanical gardens, schools for the children of nobles and commoners alike, and a sanitation system that put European cities to shame. Its rulers were literate, its astronomers kept an accurate calendar, and its poets composed verse that survives.
Two years
Hernan Cortes landed on the Gulf coast in 1519 with about five hundred men, sixteen horses and a few cannon. He could not have taken the empire with that, and he did not. What he had was the empire's enemies. The Tlaxcalans, after fighting him, allied with him and supplied tens of thousands of warriors; so did other subject cities glad to see the Mexica humbled. The emperor Moctezuma admitted the Spaniards to the city, was taken hostage, and died in the fighting that followed in 1520, when the Spaniards were driven out with heavy losses on the night the Mexica called the sorrowful night.
Cortes returned in 1521 with his allies, built boats to control the lake, cut the causeways and the aqueduct, and besieged the city for three months. By then smallpox, brought by a Spanish soldier the previous year, had swept through a population with no immunity and killed a large part of it, including the new emperor. Tenochtitlan fell on 13 August 1521 after house-to-house fighting that left it in ruins. The causes, in rough order of weight:
- •Tens of thousands of indigenous allies who wanted the Mexica gone
- •Smallpox, which killed perhaps a third of the population during the siege
- •Steel, horses, cannon and ships on the lake, decisive in the final assault
- •An empire of tribute rather than integration, with no loyalty to draw on
- •A political crisis at the top after Moctezuma's death
What survived
The Spanish built Mexico City on the ruins, and the Great Temple lies under its central square, excavated since 1978. Nahuatl is still spoken by more than a million people. The chinampas survive at Xochimilco, still farmed. The foods the Mexica cultivated, maize, beans, chillies, tomatoes, cacao, avocados and vanilla, went on to change the diet of the world. And the eagle on the cactus that the priests saw in 1325 is on the flag of Mexico.
The takeaway
The Mexica rose from migrants on a marsh to rulers of central Mexico in two centuries through the Triple Alliance and a system of tribute enforced by constant war, and built in Tenochtitlan one of the great cities of the world. The same system left them surrounded by enemies, and when the Spanish arrived with steel, smallpox and, above all, tens of thousands of indigenous allies, the empire was gone in two years.